Supportive treatment for Yellow Fever means treating symptoms and protecting organs while the virus runs its course: doctors give IV/oral fluids and electrolytes, manage nausea/vomiting, maintain blood pressure and oxygen, and monitor liver, kidney, and clotting closely; paracetamol/acetaminophen is used for fever and pain (and aspirin/ibuprofen are usually avoided because of bleeding risk), while severe cases may need vasopressors, blood/platelet transfusions, dialysis, ventilator support, careful glucose control, and treatment of secondary bacterial infections if suspected.